Los Angeles' cold case detectives developed a break in the case after they screened potential forensic leads under a grant from National Institute of Justice's "Solving Cold Cases with DNA" program, authorities said.

"DNA evidence did play a key factor in this case getting solved," the police said in a statement.

Stumler was killed in his apartment in the west Los Angeles area and was discovered by a friend who checked on him after Stumler failed to report to his full-time job at the Los Angeles County Housing Authority, police said.

Stumler held a side job as a boxing manager and was managing Speight as one of his boxers for about two years, police said.

Stumler, a native of New Albany, Indiana, moved to Los Angeles after graduating from the University of Indiana about six years before his death, police said.